KR100648301B1 - Canister with capacitive level sensor for the special chemical - Google Patents

Abstract

A chemicals storage container having a capacitive level sensor is provided to facilitate mechanical and electrical sealing of metal probe, to supply a chemicals storage container resistant to vacuum or high pressure, to allow precise measuring of precursor liquid level, and to improve accuracy of capacity measuring by stabilizing liquid surface of precursor. The chemicals storage container having the capacitive level sensor for easy sealing of metal probe and precise measuring of precursor liquid level includes: a case(11) where precursor is stored, a main body of container(10) including a cover(12) combined to the upper part of the case(11); an inlet pipe(20) injecting inactive gas into the container, which is connected to the cover(12); an outlet pipe(30) discharging injected inactive gas and evaporated precursors, which is connected to the cover(12); and a capacitive level sensor measuring liquid level of precursors inside the container through capacity difference between the first probe(60) and the second probe.

Description

Chemical storage container with capacitive level sensor {Canister with Capacitive level sensor for the special chemical}

1 is a cross-sectional view schematically showing an example of a conventional precursor storage container.

2 is a view schematically showing another example of a conventional precursor container.

3 is a view schematically showing another example of a conventional precursor container.

Figure 4 schematically shows a precursor storage container equipped with a conventional capacitive level sensor.

5 is an enlarged cross-sectional view of the probe of the capacitive level sensor shown in FIG.

Figure 6 is a schematic view showing a precursor storage container equipped with a capacitive level sensor according to a first embodiment of the present invention.

7 is an enlarged cross-sectional view of the probe of the capacitive level sensor shown in FIG.

8 is a schematic view showing a precursor storage container equipped with a capacitive level sensor according to a second embodiment of the present invention.

9 is a schematic view showing a precursor storage container equipped with a capacitive level sensor according to a third embodiment of the present invention.

10 is a schematic view showing a precursor storage container equipped with a capacitive level sensor according to a fourth embodiment of the present invention.

11 is a view schematically showing a precursor storage container equipped with a capacitive level sensor according to a fifth embodiment of the present invention.

12 is a schematic view showing a precursor storage container equipped with a capacitive level sensor according to a sixth embodiment of the present invention.

Figure 13 is a schematic view showing an experimental device for measuring the liquid level using the drug storage container.

14 is a graph showing the liquid level measurement results of the chemical storage container is installed metal tube outside the metal probe.

15 is a graph showing the liquid level measurement results of the chemical storage container without a metal tube installed outside the metal probe.

<Explanation of symbols for main parts of the drawings>

10: container body 11: case 12: cover

13 coupling port 20 injection pipe 30 discharge pipe

50 capacitive level sensor 51 controller

60,60a: probe 61,61a: metal probe 62: connector

63: upper gasket 64: lower gasket 65: grand

66: nut part 67: fixing nut 70: metal tube

71: through hole 72: inlet hole 81: point level sensor

82: ultrasonic level sensor

The present invention relates to a chemical storage container having a capacitive level sensor, and more particularly, to a liquid chemical stored in a storage container used to store or handle various chemicals used in the manufacture of semiconductors or electronic materials. In the capacitive level sensor installed to measure the liquid level of the chemical, the structural change of the probe enables simultaneous electrical disconnection and mechanical closure, minimizing errors in the liquid level measurement, so that the chemical capacity in the container can be measured more accurately. Chemical storage with a capacitive level sensor for liquid level measurement that prevents depletion or overcharging of chemicals in the process of manufacturing semiconductors or electronic materials to enable stable operation in the use of semiconductor or electronic materials manufacturing equipment. It's about courage.

In general, in the manufacturing process related to semiconductor and electronic materials, an atomic layer using an organic metal compound or an inorganic metal compound (hereinafter referred to as a 'precursor') when depositing a metal thin film, a metal nitride thin film, a ceramic thin film such as a metal oxide thin film, and a thick film. Processes such as atomic layer deposition (ALD) or chemical vapor deposition (CVD) are used. In the process such as ALD and CVD, precursors specially designed as core materials are used, and these precursors are filled in stainless steel or quartz storage containers specially manufactured according to the purpose, and applied to the process.

The storage container used in the apparatus for manufacturing a semiconductor device and an electronic material generally includes a case 111 in which a precursor is contained therein as shown in FIG. 1, and a cover 112 coupled to an upper portion of the case 111. The container body 110 and the cover 112 is connected to the inlet gas 120 is injected inert gas into the container body 110, the cover 112 is connected to the inert gas and the vaporized inert gas A discharge pipe 130 through which the precursor is discharged is provided.

Here, an inert gas such as argon (Ar) or nitrogen (N ₂ ) is injected into the container through the injection tube 120 to smoothly vaporize the precursor filled in the container body 110, and the injected gas is injected into the precursor. Bubbling (bubbling) to help vaporize the precursor, the gas phase of the vaporized precursor is configured to be discharged through the discharge pipe 130 in a mixed state with an inert gas and then supplied to the desired device of the semiconductor and electronic device manufacturing process.

At this time, the injection tube 120 may be formed as shown in Figure 2 according to the vaporization characteristics of the precursor stored in the container body 110. That is, when the precursor has excellent vaporization characteristics, the precursor is not required to be bubbled separately, so when the transport gas is injected, the transport gas is discharged through the discharge pipe 130 together with the gas phase of the vaporized precursor, It is configured to supply up to the desired device.

Regardless of the length of the injection tube 120, the above storage containers consume precursors in the process of manufacturing a semiconductor or an electronic material. Accordingly, the precursors need to be filled in the container body 110 according to the degree of precursor consumption. And, for this purpose it is also used that the filling hole 140 is formed in the cover 112 as shown in FIG.

However, the conventional drug storage containers shown in Figures 1 to 3 described above are generally used to have a structure that is not visible inside, so the amount of precursor stored in the container body 110 cannot be accurately determined with the naked eye. Therefore, the number of semiconductor wafers produced through the CVD equipment is counted to estimate the amount of precursors used in the production of the wafers.In accordance with the expected results, the containers may be replaced in advance by considering the remaining amount before the precursors in the container are depleted. Recharging Therefore, even if there is a sufficient amount of precursor inside the container body 110, it is impossible to accurately check, so frequent replacement of the container occurs, or because the precursor inside the container is depleted and operating the equipment in the absence of the precursor is defective There is a problem that a lot of damage occurs in terms of money and time by making a wafer.

In order to solve this problem, recently, a storage container equipped with various types of level sensors capable of measuring the amount of precursor therein is used. As the level sensor used for the storage container, a float type level sensor or a point level sensor is generally used. Here, the float level sensor is a sensor for floating the annular float ball in the precursor solution to detect the capacity of the precursor by detecting the proximity of the float ball when the position of the float ball is moved, the point level sensor is a liquid at a predetermined position When is reached, it is an electric or electronic signal that is delivered to the desired device to check the capacity of the precursor inside the container.

However, the method of using the float ball has a limitation on the float ball movement when using a viscous liquid, and the magnetic flux density of the magnet installed inside the float ball decreases when used at high temperature, so the detection by the proximity sensor is performed. In particular, the buoyancy of the float ball is weakened in the process of bubbling the precursor by injecting gas into the storage container, and discharging the gas phase of the vaporized vaporized precursor into the discharge pipe 130 mixed with an inert gas. Due to problems such as the float ball sinking, it is likely to cause errors when measuring the liquid level inside the container. In addition, the point level sensor has a disadvantage that it is difficult to monitor the precursor in the container in real time. Therefore, a new type of liquid level measurement method is required.

Therefore, in recent years, as shown in FIGS. 4 and 5, the capacitance between the two probes is measured, and the capacitive level sensor 150 for measuring the liquid level inside the storage container through this is more precisely installed in the storage container. A method capable of measuring the precursor liquid level inside the container body 110 is used.

The storage container equipped with such a capacitive level sensor 150 is installed in the container with a probe 160 with a metal probe 161 and used as the first probe, the container body 110 as a second probe By using the controller to measure the capacitance changes according to the change in the liquid level inside to measure the precursor level inside the storage container through this. Here, the contact of the second probe is electrically connected to the cover 112, as shown in the figure, the cover 112 is connected to the case 111, so the second probe is the cover 112 and the case ( 111) to the container body containing. At this time, the controller 151 is a device that is generally used to measure the change in capacitance and to collectively monitor the precursor liquid level inside the storage container.

Probe 160 in the capacitive level sensor 150 is known in a variety of forms, but generally as shown in Figure 5 metal probe 161 is connected to the wire at the top; A gasket 163 wrapped around an upper outer periphery of the metal probe 161 for insulation; A gland 165 wrapped around the gasket 163 and having a locking jaw formed at a lower end thereof; In order to insulate and seal the metal probe 161, the glass material 164 formed by welding the gland 165 and the gripping jaw of the gland 165 are caught. It is configured to include a fixing nut 167 is coupled to the 113.

Probe 160 of the above configuration is that the fixing nut 167 is coupled to the coupling port 113 of the cover 120 of the storage container, the metal probe 161 is located inside the storage container, the metal probe 161 The wire connected to the upper end of the is connected to the monitoring device, it is typically to measure the liquid level inside the container body 110 through the capacitance between the metal probe 161 and the container itself. In this case, the capacitance value measured by the capacitive level sensor 160 affects not only the container body 110 including the cover 112 and the case 111 but also the peripheral elements such as the precursor and the metal probe 161. In order to measure the capacitance more precisely, electrical disconnection and mechanical sealing between the metal probe 161 and the container itself are very important.

The gasket 163 and the glass material 164 is formed for electrical disconnection and mechanical sealing between the probe 160 and the gland 165 made of a metal material, and the glass material 164 is a welding method. Formed by a hermetically seal. However, as described above, the glass material 164 formed between the gland 165 and the metal probe 161 has an impact or instantaneous high pressure on the container or probe 160 due to its physical properties. If this is applied, there is a risk of breakage, and in this case, chemicals inside the metal container are likely to leak to the outside, causing a serious danger. In addition, when the sealing process between the metal and the glass material 164 by a welding method, various additives are used for the buffer against thermal expansion during special welding of the glass material, these additives are reacted with the chemical and stored in the metal container The reality is that there are various problems such as the possibility of chemical deterioration.

In addition, the capacitance value measured by the capacitive level sensor 160 mounted in the precursor storage container is affected throughout the peripheral element as described above, especially when the case 111 of the storage container is cylindrical, Capacity values are also affected by cylindrical walls and flat bottoms. In particular, in the upper level of the precursor filled inside the container body 110 of the storage container is affected by the wall surface of the side of the case 111, while outputting an error-free value, as the lower level toward the lower level than the wall surface of the case 111 Since the surface is more affected, the distorted capacitance value is output differently from the actual level, which makes it difficult to accurately measure the liquid level inside the storage container.

In addition, the precursor storage container equipped with the capacitive level sensor 150 is essentially subjected to a bubbling process, a transfer gas injection and a mixed gas discharge process, and a recharging process when used in the process of manufacturing a semiconductor or electronic material. In this process, the surface of the precursor liquid level is shaken so that the precursor may be buried on the surface of the metal probe 161 of the probe 160 at a position higher or lower than the actual precursor level. There is a disadvantage that it is difficult to accurately measure the precursor level in the storage container accordingly. In particular, when the capacitive level sensor 150 recognizes that the capacity of the precursor is insufficient due to the wave of the liquid surface in the refilling process, a situation may occur in which the precursor continues to be charged through the charging port 140 to be charged above the maximum capacity. In this case, there is a problem that a fire may occur in the equipment due to the leakage of the precursor during the process.

Accordingly, the present invention has been made in order to solve the above-mentioned problems, the capacitive level used to measure the liquid level of the liquid precursor stored in a metal storage container that is essential for the use of the precursor in the manufacture of electronic materials By improving the probe structure in the sensor, it is easy to achieve mechanical and electrical sealing of metal probes, and to provide a chemical storage container with a capacitive level sensor that can withstand vacuum or high pressure. have.

In addition, in the present invention, it is possible to measure the liquid level of the precursor more accurately by preventing the distortion of the capacitance value at a lower level, and to stabilize the liquid level of the precursor inside the container in any process of manufacturing a semiconductor or an electronic material. Another object is to provide a chemical storage container equipped with a capacitive level sensor to increase the accuracy of the capacitance value.

In addition, the present invention provides a chemical storage container having a capacitive level sensor mounted in parallel with the capacitive level sensor in order to more accurately measure the liquid level of the precursor inside the storage container. There is another purpose.

In order to achieve the above object, the present invention provides a container body including a case in which a precursor is contained therein and a cover coupled to an upper portion of the case, and an injection tube connected to the cover to inject an inert gas into the container. A chemical storage container connected to the cover and including a discharge pipe through which the injected inert gas and the vaporized precursor are discharged, and a capacitive level sensor for measuring the liquid level inside the container through the capacitance between the first probe and the second probe. The probe comprising: a metal probe; A connector coupled to an upper end of the metal probe; Upper and lower gaskets wrapped around an upper outer periphery to insulate the metal probe; A gland wrapped around the bottom of the lower gasket and having a locking jaw formed at a lower end thereof; An upper end portion is wrapped around the upper gasket for sealing, and a lower end portion is coupled to an upper portion of the gland; The drug storage container having a capacitive level sensor, characterized in that it comprises; a fixing nut is caught on the gripping jaw of the grand, the inner bottom is coupled to the coupling hole of the cover.

In addition, the present invention is characterized in that it comprises a circular metal tube which is installed on the outside of the metal probe to allow the introduction of the precursor into the inside while performing the role of the second probe while stabilizing the liquid level of the precursor introduced into the inside. To provide a chemical storage container having a capacitive level sensor.

The present invention also provides a chemical storage container having a capacitive level sensor, characterized in that the auxiliary level sensor is provided with the capacitive level sensor.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

6 is a view schematically showing a precursor storage container equipped with a capacitive level sensor according to the first embodiment of the present invention, and FIG. 7 is an enlarged cross-sectional view of a probe of the capacitive level sensor shown in FIG. 6.

As shown in FIGS. 6 and 7, the precursor storage container equipped with the capacitive level sensor 50 includes a case 11 in which a precursor is contained therein and a cover 12 coupled to an upper portion of the case 11. A container body 10 including a), an injection tube 20 connected to the cover 12 and an inert gas is injected into the container, and connected to the cover 12 and an inert gas and a vaporized precursor It is configured to include a capacitive level sensor 50 for measuring the liquid level in the container through the discharge pipe 30 and the capacitance between the first probe 60 and the second probe discharged.

Here, the container body 10, the injection pipe 20, and the discharge pipe 30 formed of the case 11 and the cover 12 can be easily formed by applying the prior art, and if necessary, Filling ports (not shown) may be provided for charging. In addition, the precursors stored in the container body 10 collectively refer to organometallic compounds or inorganic metal compounds used to form metal thin films, metal nitride thin films, metal oxide thin films, etc. in semiconductor and electronic material manufacturing processes. Therefore, it is noted that it may be a drug other than. In addition, the injection tube 20 may have a long or short internal length depending on the vaporization characteristics of the precursor filled in the storage container. That is, when the vaporization characteristics of the precursor is not good, the injection into the inside of the storage container as shown in the drawing to perform the bubbling process of vaporizing the precursor by the injected gas to be discharged to the discharge pipe 30 together with the injected gas. The length of the tube 20 can be formed long, on the contrary, when the transport gas is injected without a separate bubbling process due to excellent vaporization characteristics of the precursor, the transport gas is discharged through the discharge pipe 30 together with the gas phase of the vaporized precursor. In order to perform the injection of the transport gas and the discharge of the mixed gas, the length of the injection pipe 20 inside the storage container may be short as described in the related art. The selection of such a container can be easily selected and used by those of ordinary skill in the art.

In this case, according to the present invention, the probe 60 used as the first probe in the capacitive level sensor 50 is a metal probe 61 and a connector to which a wire is connected to be coupled to an upper end of the metal probe 61. 62), upper and lower gaskets 63 and 64 wrapped around an upper outer circumference for insulation of the metal probe 61, and a gland that is wrapped around the lower gasket 64 and has a locking step formed at a lower end thereof. 65 and an upper end portion is enclosed outside the upper gasket 63 for sealing, and a lower end portion is connected to an upper portion of the gland 65 and a nut part 66 coupled to an upper end of the gland 65. Hanging, the inner bottom includes a fixing nut 67 is coupled to the coupler 13 of the cover 12.

Here, the connector 62 coupled to the upper end of the metal probe 61 is formed to easily connect the metal probe 61 and the controller 51 to the metal of the same material as the metal probe 61. It is good to be produced. In this case, the metal probe 61 may be used for a conventional probe 60, and may be made of stainless steel, nickel alloy, or the like.

In the present invention, while forming the upper and lower gaskets (63, 64) wrapped around the upper outer periphery of the metal probe 61 for electrical sealing and mechanical sealing of the metal probe 61, the lower gasket (64) Is wrapped with a gland 65 and the upper gasket 63 is wrapped with a nut 66.

In this way, when the upper and lower gaskets 63 and 64 made of an insulating material are used, electrical disconnection between the metal probe 61 and the gland 65 can be achieved, and the upper gasket 63 is pressed by the nut part 66. In addition, the lower gasket 64 may be pressed into the gland 65 to more completely seal the metal probe 61. Such mechanical sealing and electrical disconnection of the metal probe 61 increases the accuracy of the capacitance measurement value.

In this case, the upper and lower gaskets (63, 64) is preferably made of a chemically stable Teflon-based plastic insulating material, more preferably polytetrafluoroethylene (poly (tetrafluoroethylene), polychlorotriflo In poly (chlorotrifluoroethylene), poly (vinylidenefluoride), perfluoroalkoxy, or a mixture of polytetrafluoroethylene and poly (perfluoropropylvinylether) It is better to use the selected one.

As described above, when the upper and lower gaskets 63 and 64 are used for sealing the metal probe 61, a Teflon-based plastic insulating material exhibits superior characteristics compared to those of conventional glass materials. That is, the glass material has a risk of being damaged when a shock or instantaneous high pressure is applied to the container or the probe 60 during movement or use due to its physical properties. However, as in the present invention, Teflon-based plastic insulation is used. This risk is eliminated. In addition, it is possible to ensure excellent sealing properties without the sealing treatment by the welding method it is possible to prevent the deterioration of chemicals stored in the container body 10 by the conventional welding.

The fixing nut 67 is formed to be coupled to the storage container so that the probe 60 can be mounted, and the fixing nut 67 is caught on the locking jaw of the grand 65 and a spiral groove Is formed is coupled to the coupling sphere 13 and the spiral formed on the cover 12 of the storage container.

In the storage container equipped with the probe 60 having the above structure, the probe 60 is used as the first probe, and the second probe may be applied to the general method of using the container body 10 as shown in the drawing. In addition, the liquid level inside the container body 10 may be measured through the capacitance between the container body 10 and the metal probe 61. The controller 51 formed between the first probe 60 and the second probe generally refers to a device that can measure the change in capacitance and thereby monitor the precursor level inside the container body 10. The device is in use.

In the case of the precursor storage container equipped with the capacitive level sensor 50 having the probe 60 according to the present invention as described above, it is possible to effectively obtain electrical disconnection and mechanical sealing of the metal probe 61. More accurate capacitance values can be measured compared to storage containers. In addition, by using the Teflon-based plastic insulating material as the upper and lower gaskets (63, 64), there is no risk of being damaged even when a shock or momentary high pressure is applied to the storage container.

On the other hand, the capacitance value measured by the capacitive level sensor 60 mounted in the precursor storage container is output at the upper level is error-free due to a lot of influence of the wall surface of the side of the case 11, whereas the case at the lower level Since it is more affected by the bottom surface than the wall surface of (11), the distorted capacitance value is output unlike the actual level, making it difficult to accurately measure the liquid level inside the container body 10. In addition, when the precursor storage container equipped with the capacitive level sensor 50 is used in the process of manufacturing a semiconductor or electronic material, it is essentially subjected to a bubbling process, a transfer gas injection and a mixed gas discharge process, and a recharging process. The surface of the precursor liquid is shaken at the surface of the metal probe 61 of the probe 60 so that the precursor is buried at a position higher or lower than the actual precursor level, thereby causing an error in the capacitance value. It is disadvantageous that accurate measurement of the precursor level inside is difficult.

In order to solve this problem, in the present invention, the level of the precursor liquid around the metal probe 61 can be stabilized, and a capacitive level sensor 50 provided with a circular metal tube that can serve as a second probe is provided. Provide a medicine container.

FIG. 8 is a view schematically showing a precursor storage container equipped with a capacitive level sensor according to a second embodiment of the present invention. As shown in the drawing, a circular metal tube 70 is formed outside the metal probe 61. ) Is installed.

In this case, the metal tube 70 is connected to the container body 10 to perform a role as a second probe, so as shown in the figure, a circular metal tube 70 outside the metal probe 61. When the metal tube 70 serves as the second probe when the capacitance is installed, the capacitance value is not only at the upper level but also at the lower level, so that the metal probe 61 is affected by the metal tube 70 rather than the bottom surface. Since it is possible to eliminate the capacitance with the bottom surface, it is possible to prevent the capacitance value from being distorted at a lower level, so that the liquid level of the precursor can be more accurately measured without generating an error. For reference, the capacitance value is proportional to the surface area of the probe as is well known and inversely proportional to the linear distance between the probes. Therefore, when the metal tube 70 is installed, the distance from the metal probe 61 becomes closer to the capacitance value. This increase can be obtained a more certain value, the relationship between the metal probe 61 and the bottom is hardly affected by the interference caused by the metal tube 70 installed on the outside of the metal probe 61.

In this case, the metal tube 70 is capable of introducing a precursor into the inside, and the precursor introduced into the inside stabilizes the liquid level in any process of manufacturing a semiconductor or electronic material, thereby increasing the accuracy of the capacitance value. do. That is, when the metal tube 70 is used to manufacture a semiconductor device and an electronic material in a storage container formed on the outside of the metal probe 61, a bubbling process, a transfer gas injection and a mixed gas discharge process, and a precursor refilling process are performed. Nevertheless, the precursor existing outside the metal tube 70 may generate waves or bubbles in the upper part of the process, whereas the precursor present inside the metal tube 70 may contain waves or bubbles inside the metal tube 70. It keeps the constant level at all times because it prevents it from being transferred or inflowed. Therefore, the surrounding liquid level of the metal probe 61 is kept constant, so that the occurrence of an error in the capacitance value is suppressed, thereby enabling accurate measurement of the precursor liquid level inside the storage container.

The metal tube 70 is mounted to enable the inflow of the precursor to the inside to facilitate the flow of the precursor filled in the container body 10 to measure the actual liquid level. To this end, various mounting structures may be sought. As shown in the drawing, one end of the metal tube 70 is fixed to the cover 12, and the other end is spaced apart from the bottom surface of the case 11 by a predetermined distance. In addition to the through hole 71 is formed. Here, the through hole 71 is formed so that the pressure inside of the metal tube 70 is naturally changed according to the pressure change outside the metal tube 70 so that the precursor naturally flows in and out of the metal tube 70.

The metal tube 70 may include a general material applied to the manufacture of a chemical storage container, including stainless steel, preferably made of the same material as the container body (10). In addition, the method of fixing the metal tube 70 inside the container body 10 may be fixed by various methods, including a method of fixing by welding or making a groove.

9 is a schematic view showing a precursor storage container equipped with a capacitive level sensor according to a third embodiment of the present invention. As shown in the drawing, the metal tube 70 installed outside the metal probe 61 is shown. One end is spaced apart from the cover 12 by a predetermined distance, the other end is fixed to the bottom surface inside the case 11, and the inlet hole 72 is formed so that the precursor is introduced into the lower end.

Here, the precursor is introduced into the interior through the inlet hole 72 of the lower end of the metal tube 70, the precursor introduced into the interior of the liquid level is stabilized by any process in the process of manufacturing a semiconductor device and electronic material This maintains a constant liquid level, thereby suppressing the occurrence of an error in the measured capacitance value, thereby enabling accurate measurement of the precursor liquid level inside the storage container.

In addition, since the metal tube 70 is connected to the container body 10 and serves as a second probe, the capacitance is not only at the upper level but also at the lower level. Since the metal tube 70 is more affected by the bottom surface than the bottom surface, it is possible to exclude the capacitance from the bottom surface, thereby preventing the capacitance value from being distorted even at a lower level. You can do it.

In the case of the storage container described above, in addition to using the container body 10 as the second probe, various applications may be applied as the second probe.

FIG. 10 is a view schematically showing a precursor storage container equipped with a capacitive level sensor according to a fourth embodiment of the present invention. As shown in the drawing, the second probe 60a having the same structure as the probe 60 is shown. ) Can be used as a second probe.

In this case, it is possible to measure the precursor liquid level inside the storage container through the capacitance between the metal probe 61 of the probe 60 and the metal probe 61a of the second probe 60a, and the metal probes 61 and 61a. ) Excellent electrical disconnection and mechanical sealability allow accurate measurement of capacitance, allowing accurate measurement of precursor liquid levels in storage vessels.

In this case, as described above, the metal probes 61 and 61a of the probe 60 and the second probe 60a can perform a more accurate liquid level measurement at a lower level and also manufacture any semiconductor or electronic material. Even in this case, it is possible to install a circular metal tube to stabilize the liquid level of the precursor introduced into the outside to stabilize the liquid level of the precursor inside the container to increase the accuracy of the measured capacitance value.

FIG. 11 is a view schematically showing a precursor storage container equipped with a capacitive level sensor according to a fifth embodiment of the present invention. As shown in the drawing, a probe 60 used as a first probe and a second probe, One metal tube 70 is installed outside the metal probes 61 and 61a of the 60a to enable the precursor to flow therein.

In this case, the metal tube 70 may be mounted inside the container body 10 in various ways as described above, and when the metal tube 70 is installed, the metal probes 61 and 61a may be the container body 10. ) Precursors stored inside are minimized at the lower level as well as at the lower level, allowing accurate measurement without distortion of the measured capacitance value, thus enabling more accurate measurement of the liquid level. In addition, in any process of manufacturing a semiconductor or electronic material, the liquid level of the precursor inside the container is stabilized, thereby increasing the accuracy of the measured capacitance value, thereby making it possible to more accurately measure the liquid level.

FIG. 12 is a view schematically showing a precursor storage container equipped with a capacitive level sensor according to a sixth embodiment of the present invention. As shown in the drawing, the electrostatic storage having the probe 60 according to the present invention is stored in the storage container. The auxiliary level sensor is provided together with the capacitive level sensor 50.

The auxiliary level sensor helps to more accurately measure the liquid level of the precursor inside the container body 10, and serves to assist when one level sensor is unable to operate due to failure or the like. The auxiliary level sensor may be selected from the point level sensor 81 or the ultrasonic level sensor 82 used when measuring the internal liquid level of a conventional precursor storage container. Here, the point level sensor 81 sends a signal to an external related device when the liquid level of the precursor reaches the preset level, and the ultrasonic level sensor 82 is attached to the lower end of the case 11 to ultrasonic After sending the inside to measure the ultrasonic waves coming back to tell the level of the precursor of the fluctuating precursor inside the container body (10) continuously.

As described above, even when the auxiliary level sensor is provided, the metal tube 61 may be installed on the outer side of the metal probe 61, and another additional probe 60 may be installed and used as the second probe. This can be done selectively.

When the probe 60 is mounted in the chemical storage container according to the present invention, and the metal tube 70 is installed outside the metal probe 61 of the mounted probe 60, the accuracy of the liquid level measurement when not installed and In order to check the stability of the liquid level was carried out the following experiment.

Experimental Example

As shown in FIG. 13, the probe 60 is mounted on the container body 10 of the chemical storage container, the metal tube 70 is installed outside the metal probe 61 of the probe 60, and the metal probe 61 is installed. ) And the container body 10 to the controller 51 to measure the capacitance. The controller 51 is connected to the measuring instrument 220 and the computer 230, respectively, so that the liquid level in the container can be graphed based on the measured capacitance. After installing as described above, the hexane is filled into the inside of the chemical storage container, and then the inlet port 20 is injected with argon gas stored in the tank 210 to allow the liquid level inside to shake while the outlet connected to the vacuum pump 240. The liquid level was continuously measured at 10 second intervals while repeating the opening and closing of the valve of 30 and the results are shown in FIG. 14.

Comparative Example

The liquid level was measured in the same manner as in the experimental example using a chemical storage container without a metal tube installed, and the results are shown in FIG. 15.

As a result of the above Experimental Example and Comparative Experimental Example FIG. 15 showing the result of measuring the liquid level of the chemical storage container without the metal tube, it can be seen that an error occurs in the lower level, but the metal tube is installed as in the present invention In the case of FIG. 14 showing the liquid level measurement result of one drug storage container, it can be seen that an error of the measured liquid level value is eliminated even at a lower level, thereby making it possible to accurately measure the liquid level.

As described above, the present invention improves the probe structure of the capacitive level sensor used to measure the liquid level of the liquid precursor stored in the metal storage container essential for the use of the precursor in the manufacture of electronic materials. In addition, chemically stable Teflon-based plastic insulators can be used to facilitate mechanical sealing and electrical insulation of metal probes, as well as chemical storage containers with capacitive level sensors that can withstand vacuum or high pressure. It has a useful effect.

In addition, in the present invention, the precursor can be introduced into the outside of the metal probe of the probe and the metal tube serving as the second probe is installed, thereby eliminating the capacitance value between the metal probe and the bottom surface, thereby preventing static electricity at a lower level. By preventing the distortion of the capacitance value, the level of the precursor can be measured more accurately, and the level of the precursor within the metal tube can be stabilized in any process of manufacturing semiconductor or electronic materials, thereby increasing the accuracy of the measured capacitance value. There is a useful effect of providing a chemical storage container with a capacitive level sensor.

In addition, the present invention is useful for providing a chemical storage container having a capacitive level sensor mounted in parallel with the capacitive level sensor in order to more accurately measure the liquid level of the precursor inside the storage container. It works.

The present invention has been described above with reference to the preferred embodiments shown in the drawings, which are merely exemplary, and thus, the present invention may be variously modified and equivalently carried out by those skilled in the art. It should be interpreted by the claims intended to cover examples.

Claims (19)

A container body including a case in which a precursor is contained therein and a cover coupled to an upper portion of the case, an injection tube connected to the cover to inert gas into the container, and connected to the cover and vaporized with an inert gas injected to the cover In the drug storage container comprising a discharge pipe for discharging the precursor and a capacitive level sensor for measuring the liquid level inside the container through the capacitance between the first probe and the second probe, The probe comprises: a metal probe; A connector coupled to an upper end of the metal probe; Upper and lower gaskets wrapped around an upper outer periphery to insulate the metal probe; A gland wrapped around the bottom of the lower gasket and having a locking jaw formed at a lower end thereof; An upper end portion is wrapped around the upper gasket for sealing, and a lower end portion is coupled to an upper portion of the gland; The drug storage container having a capacitive level sensor, characterized in that it comprises; a fixing nut is caught on the gripping jaw of the grand, the inner bottom is coupled to the coupler of the cover. The method according to claim 1, The upper and lower gaskets are chemical storage containers with a capacitive level sensor, characterized in that made of a plastic insulating material of the Teflon series. The method according to claim 2, The Teflon-based plastic insulating material is polytetrafluoroethylene (poly (tetrafluoroethylene), polychlorotrifluoroethylene (poly (chlorotrifluoroethylene)), polyvinylidene fluoride (poly (vinylidenefluoride)), perfluoroalkoxy Or a polytetrafluoroethylene and poly (perfluoropropylvinylether) mixture. The method according to any one of claims 1 to 3, Capacitive level, characterized in that it comprises a circular metal tube which is installed on the outside of the metal probe to allow the introduction of the precursor into the inside to stabilize the liquid level of the precursor introduced into the inside while serving as a second probe Chemical container with sensor. The method according to claim 4, The metal tube is the upper end is fixed to the cover, the lower end is formed spaced apart from the bottom surface inside the container body, the upper end of the chemical storage container with a capacitive level sensor, characterized in that the through-hole is formed. The method according to claim 4, The metal tube is a top of the spaced apart from the cover, the bottom is fixed to the bottom surface inside the container body, the lower end of the chemical storage container with a capacitive level sensor, characterized in that the precursor inlet is formed. The method according to any one of claims 1 to 3, And a second probe mounted on the second probe to measure the liquid level in the container through the capacitance between the metal probes. The method according to claim 7, And a circular metal tube installed outside the metal probes of the probe and the second probe to stabilize the liquid level of the precursor introduced therein. The method according to claim 8, The metal tube is the upper end is fixed to the cover, the lower end is formed spaced apart from the bottom surface inside the container body, the upper end of the chemical storage container with a capacitive level sensor, characterized in that the through-hole is formed. The method according to claim 8, The metal tube is a top of the spaced apart from the cover, the bottom is fixed to the bottom surface inside the container body, the lower end of the chemical storage container with a capacitive level sensor, characterized in that the precursor inlet is formed. The method according to any one of claims 1 to 3, A pharmaceutical storage container having a capacitive level sensor, characterized in that the auxiliary level sensor is provided with the capacitive level sensor. The method according to claim 11, A medicine storage container having a capacitive level sensor, characterized in that the auxiliary level sensor is selected from a point level sensor or an ultrasonic level sensor. The method according to claim 11, Capacitive level, characterized in that it comprises a circular metal tube which is installed on the outside of the metal probe to allow the introduction of the precursor into the inside to stabilize the liquid level of the precursor introduced into the inside while serving as a second probe Chemical container with sensor. The method according to claim 13, The metal tube is the upper end is fixed to the cover, the lower end is formed spaced apart from the bottom surface inside the container body, the upper end of the chemical storage container with a capacitive level sensor, characterized in that the through-hole is formed. The method according to claim 13, The metal tube is a top of the spaced apart from the cover, the bottom is fixed to the bottom surface inside the container body, the lower end of the chemical storage container with a capacitive level sensor, characterized in that the precursor inlet is formed. The method according to claim 11, And a second probe mounted on the second probe to measure the liquid level in the container through the capacitance between the metal probes. The method according to claim 16, And a circular metal tube installed outside the metal probes of the probe and the second probe to stabilize the liquid level of the precursor introduced therein. The method according to claim 17, The metal tube is the upper end is fixed to the cover, the lower end is formed spaced apart from the bottom surface inside the container body, the upper end of the chemical storage container with a capacitive level sensor, characterized in that the through-hole is formed. The method according to claim 17, The metal tube is a top of the spaced apart from the cover, the bottom is fixed to the bottom surface inside the container body, the lower end of the chemical storage container with a capacitive level sensor, characterized in that the precursor inlet is formed.

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